A basic process for the production of arylene sulfide polymers from polyhalo-substituted aromatic compounds by reaction with an alkali metal sulfide in a polar organic compound is disclosed in U.S. Pat. No. 3,354,129.
Poly(p-phenylene sulfide) (PPS) has been recognized as having very useful properties related to high temperature resistance and chemical resistance. PPS while partially crystalline, is also readily adapted to a variety of processing techniques utilized for thermoplastic polymers. On the other hand, there are applications wherein the impact strength or toughness of PPS needs to be increased for further development in said applications. Thus, there is a need to provide added toughness or impact strength to compositions derived from PPS.
Aromatic sulfide/sulfone polymers are also known thermoplastic materials which exhibit high temperature resistance as well as chemical resistance. These aromatic sulfide/sulfone polymers can be made according to processes disclosed in a series of patents to Robert W. Campbell, for example, U.S. Pat. No. 4,016,145.
Blends of PPS with poly(arylene sulfide/sulfone)s have been proposed in an attempt to provide compositions exhibiting the desirable properties of both components. However, such blends have not generally been successful in the achievement of the desired improvement in properties for the PPS compositions such as toughness and reduced brittleness.
Attempts at copolymerization of mixtures of the respective halogenated aromatic compounds to provide copolymers thereof have encountered difficulties because suitable polymerization conditions for the respective monomers are sufficiently different to cause poor results to be obtained in the attempted copolymerization of mixtures of dihalobenzenes and dihaloaromatic sulfones.
It is therefore an object of this invention to provide a method for producing a block copolymer composed of at least one poly(phenylene sulfide) segment and at least one poly(arylene sulfide/sulfone) segment. It is another object of this invention to provide a step-wise process for preparing a block copolymer composed of at least one poly(phenylene sulfide) segment and at least one poly(arylene sulfide/sulfone) segment wherein the poly(phenylene sulfide) segment is first prepared and then a dihaloaromatic sulfone is added and polymerized to form the poly(arylene sulfide/sulfone) segment(s). It is another object of this invention to provide coated substrates wherein said coating comprises a block copolymer composed of at least one poly(phenylene sulfide) segment and at least one poly(arylene sulfide/sulfone) segment. It is another object of this invention to provide polymer blends comprising a block copolymer composed of at least one poly(phenylene sulfide) segment and at least one poly(arylene sulfide/sulfone) segment.